CN107468327B

CN107468327B - Storage and mixing device for bone cement with pressure pump

Info

Publication number: CN107468327B
Application number: CN201710431223.7A
Authority: CN
Inventors: S·福格特; T·克卢格
Original assignee: Heraeus Medical GmbH
Current assignee: Heraeus Medical GmbH
Priority date: 2016-06-08
Filing date: 2017-06-08
Publication date: 2020-04-21
Anticipated expiration: 2037-06-08
Also published as: EP3260193B1; CA2967733C; DE102016110564A1; AU2017203745B2; AU2017203745A1; US10722855B2; JP6563978B2; JP2017217469A; US20170354939A1; CN107468327A; CA2967733A1; EP3260193A1; DE102016110564B4

Abstract

The present invention relates to a storage and mixing device for bone cement with a pressure pump. In particular, the present invention relates to a storage and mixing device for two-component polymethylmethacrylate bone cement having a cartridge with a cylindrical interior. The invention also relates to a method for mixing bone cement, in particular the matrix component of a two-component polymethylmethacrylate bone cement, using said storage and mixing device.

Description

Storage and mixing device for bone cement with pressure pump

Technical Field

The invention relates to a storage and mixing device for two-component polymethylmethacrylate bone cement having a cartridge with a cylindrical interior.

The invention also relates to a method for mixing bone cement, in particular the matrix component of a two-component polymethylmethacrylate bone cement, using such a storage and mixing device.

Background

Polymethylmethacrylate (PMMA) bone cements can be traced back to the basic works of the Charnley jazz (Sir Charnley) (Charnley, j.: anchoring of the femoral head prosthesis of the femoral shaft, journal of bone and Joint surgery (j. bone Joint Surg.)42(1960) 28-30). PMMA bone cement consists of a liquid monomer component and a powder component. The monomer component typically contains methyl methacrylate monomer and an activator (N, N-dimethyl-p-toluidine) dissolved therein. The powder component (also called bone cement powder) comprises one or more polymers produced by polymerization, preferably suspension polymerization, based on methyl methacrylate and a comonomer (e.g. styrene, methyl acrylate or similar monomers), an X-ray opaque material and an initiator dibenzoyl peroxide. When mixing the powder component with the monomer component, a plastically deformable paste (i.e. the actual bone cement, which is often referred to as bone cement paste) is obtained by swelling the polymer of the powder component in methyl methacrylate. Upon mixing the powder component with the monomer component, the N, N-dimethyl-p-toluidine activator reacts with the dibenzoyl peroxide to form free radicals. The free radicals formed initiate the free radical polymerization of methyl methacrylate. As the methyl methacrylate continues to polymerize, the viscosity of the bone cement paste increases until the paste cures.

The most commonly used monomer in polymethylmethacrylate bone cements is methyl methacrylate. Redox initiator systems generally consist of a peroxide, an accelerator and, if desired, a suitable reducing agent. Free radicals are only formed when all elements in the redox initiator system interact. Thus, the elements of the redox initiator system are arranged in the separate parent components in such a way that these elements do not trigger free-radical polymerization. The parent component may be stored stably if the composition is appropriate. Only when the two matrix components are mixed to form the cement paste does the elements of the redox initiator system previously stored separately in the two pastes, liquids or powders react to form free radicals, triggering the free radical polymerization of at least one monomer. Radical polymerization then results in the formation of a polymer using the monomers, while the cement paste hardens.

PMMA bone cement can be mixed by mixing cement powder with monomer liquid in a suitable mixing reservoir with the aid of a spatula. Here, air bubbles may be entrapped in the bone cement paste, which may negatively affect the mechanical properties of the hardened bone cement.

To avoid air inclusions in the bone cement paste, various vacuum cementing systems have been described, in which the following are listed as examples: US 6,033,105A, US 5,624,184A, US 4,671,263A, US 4,973,168A, US 5,100,241A, WO 99/67015A 1, EP 1020167A 2, US 5,586,821A, EP 1016452A 2, DE 3640279A 1, WO 94/26403A 1, EP 1005901A 2 and US 5,344,232A. For the presented vacuum cementing system, an external vacuum pump needs to be connected to generate the reduced pressure. These vacuum pumps are usually operated with compressed air using the Venturi principle (Venturi principle). The compressed air required to operate the vacuum pump is obtained from a fixed compressed air installation or from an electrically actuated compressor. Additionally, an electrically actuated vacuum pump may also be used to generate the vacuum.

A further development of the cementing technique includes cementing systems in which both cement powder and monomer liquid have been packaged in separate compartments of a mixing system and mixed together in the cementing system just before the cement is applied. Such closed fully pre-packaged mixing systems have been proposed in EP 0692229 a1, DE 102009031178B 3, US 5,997,544A, US 6,709,149B 1, DE 69812726T 2 and US 5,588,745A. These mixing systems also require an external vacuum source. From EP 0796653 a2 a device for producing bone cement from a bone cement powder and a monomer liquid in a cartridge is known, wherein a vacuum is drawn by means of an attachable vacuum plunger. A disadvantage of this system is that after the monomer liquid container has been opened or connected, the monomer liquid can already penetrate into the bone cement powder and react before the remaining monomer liquid is sucked into the cartridge by means of the vacuum plunger. Thus, hardened platelets of bone cement may be formed in the cement paste, rendering them inhomogeneous, thereby complicating the application of the bone cement paste and negatively affecting the mechanical properties of the hardened bone cement. In addition, the use of the device is relatively complex and therefore prone to errors due to the multiple steps involved in connecting the components of the device and in creating the vacuum.

Patent US 8,757,866B 2 discloses a storage and mixing device as a fully prepackaged mixing system in which the parent components required to produce the bone cement paste have been stored and may be combined and mixed in the storage and mixing device. The storage and mixing device has a two-piece delivery plunger for closing the cement cartridge. Here, a combination of a gas-permeable sterilization plunger and a gas-impermeable sealing plunger is used. The principle of closed vacuum mixing system is in closed

PRO cementation system, produced and distributed by the heili medicine gmbh (heraeus Medical gmbh).

WO 00/35506 a1 proposes a device in which polymethylmethacrylate bone cement powder is stored in a cartridge, wherein the cement powder fills the entire volume of the cartridge and the volume of the intermediate spaces between the cement powder particles corresponds to the volume of monomer liquid required to produce a bone cement paste with the cement powder stored in the cartridge. This device is structured in such a way that a vacuum introduces the monomer liquid into the cartridge from above, wherein for this purpose a vacuum is applied at a vacuum port on the underside of the cartridge. Thus, the monomer liquid is pumped through the cement powder while the air located in the intermediate spaces of the cement particles is replaced by the monomer liquid. Here, the cement paste formed was not mechanically mixed by a stirrer.

A disadvantage of this system is that cement powders that are rapidly swollen with monomer liquid cannot be mixed with this device, because the rapidly swelling cement powder particles form a gel-type barrier after penetration of the monomer liquid up to about 1 to 2cm into the cement powder and hinder movement of the monomer liquid through the entire cement powder. Furthermore, the possibility of vacuum pumping the monomer liquid out of the vacuum port after the monomer liquid has completely penetrated the cement powder cannot be excluded. Subsequently, insufficient monomer liquid is available for hardening by free-radical polymerization, or the mixing ratio and thus the consistency of the bone cement are unintentionally changed. It is also problematic that the air entrained between the cement powder particles is to be replaced from top to bottom by the monomer liquid, but since the air is significantly lighter than the monomer liquid, it tends to drift upwards in the cement powder due to gravity, rather than moving downwards in the direction of the vacuum port.

When using a vacuum mixing system for cementing, an external vacuum pump has to be provided. These vacuum pumps are expensive and must be cleaned after use. Furthermore, a vacuum hose is required to connect the vacuum pump with the vacuum mixing system. These vacuum hoses must be provided together with the vacuum mixing system. Therefore, before mixing with a vacuum mixing system, a vacuum pump must first be assembled in an operating chamber (OP chamber) and connected to a source of energy, such as compressed air or a power source. The vacuum pump is then connected to the vacuum mixing system by means of a vacuum hose. These assembly steps consume valuable OP time and are likely to be erroneous. Vacuum pumps and connections to the vacuum mixing system and to external energy sources and power supply lines require space and present a potential trip hazard and obstruction that can interfere with occasional busy procedures during operation.

EP 1886647 a1 proposes a concept of interest. Here, the cement powder is stored in an evacuated cartridge and the monomer liquid is located in a separate container. When the cartridge under reduced pressure is opened, monomer liquid is drawn into the cartridge without inflow of air. Resulting in a bone cement paste that is free of air inclusions. This concept requires that the cartridge remain closed to a vacuum seal during storage prior to use and that no sterile air can enter. For this purpose, the cartridge must be hermetically sealed in a stable manner. A disadvantage is therefore that the construction is complicated and the contents of the cartridge cannot be mixed by means of the mixing system for external operation after the monomer liquid has been aspirated into it, since the feed-through of the mixing rod or mixing tube cannot be permanently vacuum-sealed easily.

Disclosure of Invention

It is therefore an object of the present invention to overcome the disadvantages of the prior art. In particular, the disadvantages of known vacuum mixing systems having an external vacuum source are to be overcome. The aim of the invention is here, in particular, to develop a simple closed storage and mixing device in which polymethylmethacrylate bone cement powder (cement powder) and monomer liquid are stored in separate compartments and can be mixed subsequently. The medical user should be able to combine and mix the polymethylmethacrylate bone cement powder with the monomer liquid in the storage and mixing device without contacting the two parent components with the medical user. Any contact of the medical user with the polymethylmethacrylate bone cement powder and the monomer liquid should be excluded as much as possible. The device to be developed is preferably a fully prepackaged mixing system. The storage and mixing device should be designed in such a way that monomer fluid can be transferred into the polymethylmethacrylate bone cement powder without the use of an external vacuum pump actuated by compressed air or a compressor. It is also important that the storage and mixing device ensures in a practical and reliable manner that the bone cement paste is produced without an external energy source, such as compressed air, vacuum or electrical power, even under the simplest external conditions. The storage and mixing device should be autonomously usable without further technical equipment. The storage and mixing device should also be structured as simply and inexpensively as possible.

The storage and mixing device should be simplified in such a way that, with only one manually operated element, the monomer liquid container or the glass ampoule or foil pouch as monomer liquid container can be opened first and then the transfer of the monomer liquid into the cartridge with the cement powder therein can be carried out manually without using an externally generated vacuum. Malfunction should be eliminated as much as possible by the configuration.

It would also be desirable to provide a method that enables monomer liquid transfer and mixing in a fully prepackaged mixing system and wherein, after the monomer liquid container has been opened, only a single operating element has to be operated to transfer the monomer liquid, create reduced pressure in the mixing chamber (cartridge) and mix with the bone cement powder to form the desired bone cement paste. It should be possible here to produce the storage and mixing devices to be developed predominantly from inexpensive plastics.

Furthermore, it should be found that a storage and mixing device for mixing medical bone cement and a parent component for storing bone cement and a method for mixing bone cement can be produced at low cost and reliably, wherein the simplest possible manual operation for mixing the parent components can be used, as far as possible without the use of external or additional energy sources and no air inclusions are formed in the mixed product.

The first parent component of the polymethylmethacrylate bone cement as the product of the mixing should be a powder or a bone cement powder and the second parent component should be present in liquid form, i.e. a monomer liquid. Preferably, it should be possible to store the two parent components of the bone cement separately in a fully prepackaged mixing system and to combine them safely using the storage and mixing device.

The object of the invention is achieved by a storage and mixing device for two-component polymethylmethacrylate bone cement having:

a) a cartridge having a cylindrical interior, wherein the cylindrical interior is bounded on a front side by a cartridge head having a closed delivery opening,

b) a plunger arranged axially movable in the cylindrical interior of the cartridge and spaced from the cartridge head, wherein the plunger is placed circumferentially against the inner wall of the interior such that the plunger divides the interior of the cartridge into two sections,

c) a powdered first matrix component of bone cement contained within the interior between the plunger and the cartridge head,

d) a feed-through device arranged in or in a cylindrical sleeve (cylinder barrel) of the cartridge between the plunger and the cartridge head, wherein the feed-through device is connected to a fluid line,

e) a reservoir of a monomer liquid, wherein a fluid line connects the feed-through device to the reservoir in a liquid-permeable manner, wherein the monomer liquid as a second parent component of the bone cement is contained in the reservoir or is fillable or introducible into the reservoir,

f) a press-out device that can be pushed into the reservoir, so that the monomer liquid can be pressed out of the reservoir into the fluid line,

g) wherein the plunger is spaced from a back side of the cylindrical interior opposite the front side such that by moving the plunger in a back side direction the expression means can be pushed into the reservoir and a reduced pressure can be generated inside the cartridge between the plunger and the cartridge head.

When a reduced pressure has been generated in the cartridge interior between the plunger and the cartridge head as a result of said movement of the plunger, this reduced pressure passes through the feed-through and into the fluid line.

Preferably, a pump plunger is used as the expression means. It is also possible to use an elastic membrane as the expression means, wherein the elastic membrane is expanded into the reservoir (thereby being moved into the reservoir or pushed into the reservoir according to the invention), thereby pressing the monomer liquid from the reservoir into the fluid line.

Preferably, no other structural elements are provided between the plunger and the powdered first precursor component.

It is preferably provided that the first matrix component is a cement powder.

Furthermore, it can be provided that the plunger divides the cartridge interior into two sections in a gas-tight manner. This ensures that the movement of the plunger in the direction of the back side enables a reduced pressure to be generated in the cartridge interior and can be maintained at least until the end of the mixing process.

The cartridge interior has a cylindrical geometry. Cylindrical is the simplest shape that can achieve the inside of the cartridge. Geometrically, a cylinder is the shape of a general cylinder having any base area, i.e. not just a cylinder with an annular base. Thus, the inner delimiting inner wall may be a cylinder with any base and the cylindrical sleeve of the cartridge, if present, may also be a cylinder with any base, i.e. also with a non-annular or non-circular base. However, according to the invention, cylindrical geometries with rotational symmetry and in particular an annular base are preferred for the interior of the first cartridge, since these shapes are easiest to produce and the plunger is less prone to get trapped in the interior when it is moved axially in the interior. In addition, there is a low likelihood that leakage between the inner wall of the interior and the plunger may occur during plunger movement.

The fact that the plunger is axially movable in the cylindrical interior of the cartridge means that the plunger is axially movable along the cylinder axis of the cylindrical interior.

According to the invention, it can be provided that the plunger is a delivery plunger, by means of which the mixed bone cement paste can be pressed out of the cartridge through the delivery opening or through the delivery tube or hollow mixing rod by advancing the delivery plunger in the direction of the cartridge head.

The back side of the interior is also the back side of the cartridge.

In the storage and mixing device according to the invention, it can be provided that the plunger in the interior of the cartridge can be pushed or pulled manually in the direction of the back side of the interior by means of a rod or another force transmission member, wherein preferably an actuating member or a handle for operating the rod or the force transmission member is attached to the rod or the force transmission member.

In this way, the reduced pressure can be generated manually in a simple and straightforward manner, and the expression means and thus the monomer liquid can be actuated manually in a simple manner, so that on the one hand the risk of possible malfunctions is reduced, and on the other hand complex and expensive structural elements, such as motors, energy storage or controls, are avoided. In addition, this may ensure simple and safe operability of the storage and mixing device.

It can further be provided that a filter, in particular a porous filter, is arranged in the cartridge head, in the feed-through and/or in the fluid line, wherein the filter is permeable to the monomer liquid and impermeable to the pulverulent first parent component.

This prevents the cement powder or powdered first matrix component from entering the fluid line as far as the monomer liquid, where it prematurely reacts with the monomer liquid, cures or gels, and thus blocks the fluid line. For this purpose, the filter is preferably arranged in the cartridge head, in the feedthrough or in the fluid line in the region of the feedthrough.

Preferably, provision may also be made for the plunger to be spaced from the back side of the cylindrical interior at a location opposite the front side, to the extent that the reduced pressure can draw monomer liquid from the fluid line into the cartridge interior.

In this way, in addition to the delivery caused by moving the expression means into the reservoir, the stroke of the plunger is also sufficient to draw the monomer liquid into the cartridge interior through the fluid line with the aid of the reduced pressure generated in the cartridge interior.

For this purpose, it can furthermore be provided that the plunger is spaced apart from the rear side of the cylindrical interior, so that the space for displacement of the plunger to the rear side is at least equal to the volume of the monomer liquid to be sucked in, preferably at least equal to the volume of the fluid line and the reservoir.

A further development of the invention provides that the storage and mixing device has a container which is separate from the cartridge and from the reservoir and in which the monomer liquid is contained, wherein the container is connected to the reservoir in particular via an opening, wherein preferably a closed glass ampoule or a foil bag containing the monomer liquid is or can be arranged in the container, wherein the glass ampoule can be broken open in the container or the foil bag can be pierced or torn open in the container.

In this way, a so-called fully prepackaged mixing system is provided, in which all the precursor components, i.e. both precursor components (cement powder as first powdery precursor component and monomer liquid as second precursor component) are already contained in the storing and mixing device, and can also be stored therein for a longer time and can be mixed in the storing and mixing device.

In the storage and mixing device it can be provided that the cartridge, the reservoir, the individual containers and the fluid lines are connected to a common holder, wherein the reservoir, the containers and the fluid lines are permanently connected to the holder and the cartridge is detachably connected to the holder, the cartridge being screwed to the holder preferably by means of a thread or connected to the holder by means of a latching mechanism.

This simplifies the use of the storage and mixing device. In the operator's compartment, there is in most cases a plane surface, such as a table, on which the storage and mixing device can be mounted and used with the aid of a stand, without the storage and mixing device having to be held in the hand. This simplifies the use of the storage and mixing device even further.

It can furthermore be provided that the monomer liquid container, in particular a foil bag or a glass ampoule, is contained in a separate container and can be opened within the separate container such that monomer liquid flows from the opened monomer liquid container into the receptacle, wherein preferably an opening device for opening the monomer liquid container, which is operable from the outside, is arranged on the container.

In this way, a so-called fully pre-packaged mixing system is provided, in which all the parent components, i.e. the two parent components (cement powder as the first powdered parent component and monomer liquid as the second parent component), have been contained in the storing and mixing device, can be stored therein and can be mixed within the storing and mixing device. Glass ampoules or foil bags, preferably coated with aluminum, are particularly suitable for the long-term storage of the monomer liquid as the second parent component for the production of PMMA bone cement pastes. This simplifies and facilitates the use of the storage and mixing device.

In order for the monomer fluid to flow into the reservoir first, independently of other forces, the storage and mixing device must be mounted correctly so that gravity produces the desired flow direction. The terms "on top" and "on bottom" and "above" and "below" used in the context of the present invention are therefore always in relation to the correct mounting of the storage and mixing device.

A monomer liquid container having several chambers for storing monomer liquid may also be used. In the context of the present invention, a monomer liquid container is therefore also understood to be a plurality of individual partial monomer liquid containers which can be introduced into the individual containers and can be opened by means of an opening device.

It can be provided that a screen or filter is arranged in the line leading to the reservoir or also in or on the fluid line leading to the cartridge, which screen or filter can be used to retain fragments or debris of the opened monomer liquid container. The screen or filter is preferably located in the vessel, directly below the monomer liquid vessel.

A further development of the invention, which relates to the use of gravity as an actuating member for the flow of monomer liquid into the fluid line, proposes that a separate container for monomer liquid containers is arranged above the reservoir. Thus, after the monomer liquid container is opened, monomer liquid can flow downward from the monomer liquid container into the receptacle due to gravity.

According to a preferred further development of the invention, it can be provided that a mixing device is arranged inside the cartridge between the plunger and the cartridge head, by means of which mixing device the first parent component can be mixed with the monomer liquid in the cartridge interior.

In this way, the first matrix component can be mixed with the monomer liquid thoroughly in the cartridge interior to produce a bone cement paste which is as homogeneous as possible. The mixing device can preferably be operated manually from the outside.

Here, it can be provided that the mixing device can be operated from outside the cartridge by means of a mixing rod, wherein the mixing rod passes through the cartridge head in an air-tight manner and can be rotated and moved in the axial direction, the mixing rod preferably passing through the delivery opening.

In this way, the mixing device can be manually operated from outside the storage and mixing device in a simple and efficient manner. In addition, the user may accurately estimate the consistency of the bone cement paste, and thus the usability of the bone cement paste, based on the resistance to movement of the mixing device.

According to the invention, it can be provided that a fastening member, in particular an external thread, is provided on the cartridge outside in the region of the cartridge head. A separate delivery conduit may be attached to the fastening member. Preferably, however, a hollow tubular mixing rod is used, by means of which the mixing device can be operated and the plunger in the interior can be pushed in the dorsal direction of the interior to generate a reduced pressure in the interior, wherein the tubular mixing rod can be used as a delivery conduit after the closure has been removed from the tubular mixing rod. In this case, the external threads are no longer required, but they can also be used to attach the cartridge in a delivery device or an extrusion device for advancing the plunger in the direction of the cartridge head to extrude and apply the ready-mixed bone cement paste. To close the delivery opening, an extractable core material is arranged inside the hollow mixing rod, which closes the tubular mixing rod to the outside.

It can furthermore be provided that the plunger can be pushed in the direction of the rear side of the cartridge interior by means of the mixing rod.

In this way, the plunger may be actuated by the same means used to actuate the mixing device (i.e. the mixing rod) to push the expression means into the reservoir and create a reduced pressure in the interior of the cartridge. Thus, only one common device is required for two or all three functions, and only one feed-through device that must be sealed is required for the storage and mixing device for two or all three purposes.

It may furthermore be provided that the mixing rod is a delivery conduit, wherein a manually removable core material is arranged such that the mixed bone cement paste can be discharged from the interior of the cartridge through the delivery conduit without core material.

For this purpose, the delivery conduit is preferably pulled out of the cartridge interior as far as the stop in advance. If a mixing rod is used as the delivery conduit, no additional or separate delivery conduit is required that must be attached to the storage and mixing device. For this purpose, the mixing rod is guided in or through the delivery opening while sealing against the cartridge head and being axially movable and rotatable.

Alternatively, it can be provided that the storage and mixing device has a separate delivery conduit with a static mixer which can be attached to the cartridge, preferably to a fastening member on the cartridge, wherein it is particularly preferred to provide an internal thread on the delivery conduit which matches an external thread on the cartridge and/or to provide an element of the bayonet mount and/or a catch element of the catch mechanism.

The invention also proposes that, on the inside of the cartridge interior, a stop is provided on the back side, which limits the movement of the plunger in the direction of the back side.

This prevents the plunger from being displaced beyond the dorsal side of the interior and the bone cement paste from inadvertently passing to the outside.

It can also be provided that the plunger has at least one catch element, which can be detachably engaged with a complementary catch element on the cartridge inside in the rear region of the interior.

In this way, the plunger remains in place while moving as far as the back side. This prevents the plunger from being inadvertently moved while mixing the contents of the interior and from moving beyond the catch position. To deliver the ready-mixed bone cement paste, the locking mechanism can be easily disassembled.

In the storage and mixing device according to the invention, it can be provided that the cartridge, the reservoir, the cartridge head and the plunger, preferably as well as the pump plunger as the extrusion device, are made of plastic, wherein preferably the plastic is polyethylene-co-vinyl alcohol (EVOH), polybutylene terephthalate (PBT), polyethylene terephthalate (PET) and polymethyl methacrylate co-acrylonitrile.

The preferred storage and mixing device may also be characterized in that a gas-permeable opening, in particular a closable gas-permeable opening, is arranged in the cartridge head, wherein a gas-permeable and solid particle-impermeable porous disc is arranged between the first parent component and the opening, wherein the porous disc is preferably arranged in the cartridge head.

In this way, sterilization of the storage and mixing device can also be carried out with the aid of a sterilizing gas (e.g. ethylene oxide) in the cartridge interior. The opening is preferably arranged close to the delivery opening and can be closed by means of a closure.

Provision may be made for an opening to be arranged in the cartridge head above the porous disc, said opening being closable in a gastight manner and having at least 20mm²And is connected to the circumferenceAnd (4) enclosing atmosphere.

Preferably, the cartridge head is arranged at the top and the back side of the cartridge is arranged at the bottom when the storage and mixing device is properly mounted. Furthermore, the reservoir is preferably arranged below the feed-through device or at a lower level than the feed-through device. In this way, the monomer liquid cannot unintentionally flow into the cartridge, i.e. the plunger is not actuated in the direction of the cartridge back side.

Provision may also preferably be made for the monomer liquid to be introduced into the reservoir in the region of a mouth arrangement and the expression device, wherein the mouth is closed by being pushed into the expression device when the expression device starts to move into the reservoir.

This ensures that the expression means presses the monomer liquid contained in the reservoir into the fluid line rather than through the mouth.

According to a first preferred embodiment, it can be provided according to the invention that the reservoir is arranged on the cartridge back side and that the pressing-out means is pushed into the reservoir during a movement of the plunger in the direction of the cartridge back side, wherein the area between the pressing-out means and the plunger is preferably open towards the outside.

In this way, the expression means can be mechanically actuated by the plunger, whereby an extremely large force is exerted on the expression means, so that the monomer liquid can be pressed at high pressure from the reservoir through the fluid line into the cartridge interior. The fact that the area between the plunger and the expression means is open ensures that entrained air can escape, preventing said area from functioning as a gas spring, unintentionally moving the plunger back in the direction of the cartridge head, when there is little or no pressure on the expression means.

In this embodiment it can also be provided that the plunger is spaced from the expression means such that when the plunger is moved in the first section in the cartridge dorsal direction, without moving the expression means, first a reduced pressure builds up in the cartridge interior and, in addition, the expression means is pushed into the reservoir when the plunger is moved in the second section.

This ensures that the gas in the interior of the cartridge is first evacuated and can escape between the powder particles of the first parent component before the monomer liquid flows into the interior of the cartridge or is pressed into the interior of the cartridge.

It can further be provided that the expression means is a pump plunger and that the reservoir is a hollow cylinder in which the pump plunger is axially movable, wherein an extension, in particular in the form of a cylindrical body, is arranged on the upper side of the pump plunger, the outer diameter of said extension being smaller than or equal to the inner diameter of the interior of the cartridge, wherein the pump plunger with the extension is arranged in the hollow cylinder in such a way that the extension projects into the interior of the cartridge.

In this way, the pump plunger can be actuated in a simple manner by the plunger, wherein the plunger moving in the interior of the cartridge exerts a pressure on the extension of the pump plunger, thereby advancing said pump plunger in the hollow cylinder. The monomer liquid is thus pressed out of the hollow cylinder and into the cartridge through the fluid line. Thus, the plunger may then be used as a delivery plunger for expressing the mixed bone cement paste, as no accessory is located on the plunger but the accessory is mounted onto the pump plunger.

According to a second preferred alternative embodiment, it can be provided according to the invention that the receptacle is delimited by a closed hollow cylinder, said hollow cylinder being spaced from the cartridge and in which a pump plunger as an expression means is supported for axial movement, wherein the pump plunger is in circumferential and sealing contact with the inner wall of the hollow cylinder, wherein the hollow cylinder is connected to the fluid line at a first, preferably lower, base and to the interior of the cartridge at a second, preferably upper, base by means of a compressed gas or hydraulic line on the backside of the cartridge, wherein the cartridge back side is closed, except for a mouth leading into a compressed gas line or a hydraulic line, so that during movement of the plunger in the direction of the inner back side, an overpressure or pressure is generated in the space between the plunger and the rear side, said overpressure or pressure opening into the hollow cylinder via a compressed gas line or a hydraulic line.

In this way, the pump plunger in the hollow cylinder can be actuated with the aid of an overpressure or pressure which is generated by the piston movement and which is exerted on the hydraulic liquid in the space between the plunger and the back side of the cartridge. For this purpose, the pump plunger is preferably placed against a first (upper) base of the hollow cylinder and/or spaced apart from a second (lower) base of the hollow cylinder. The hollow cylinder is preferably permanently attached to the foot.

The object underlying the invention is also achieved by a method for mixing parent components of bone cement, in particular two-component polymethyl methacrylate bone cement, using a storage and mixing device according to the invention, said method being characterized by the following steps:

a) the plunger is moved in a back direction of the cylindrical interior of the cartridge, wherein a reduced pressure is generated in the cartridge interior between the plunger and the cartridge head due to said movement of the plunger,

b) due to said movement of the plunger, pushing the expression means into the reservoir, whereby due to said movement of the expression means monomer liquid contained in the reservoir is pressed through the fluid line into the cartridge interior,

c) mixing the monomer liquid with the first parent component in the interior of the cartridge to form a bone cement paste, and

d) the bone cement paste is expelled from the interior of the cartridge by advancing the plunger in the direction of the cartridge head.

Steps a) and b) can be carried out at least at times or simultaneously, while steps c) and d) are carried out one after the other and one after steps a) and b). Steps a) and b) may be performed at least occasionally or simultaneously, since the expression means is actuated occasionally or during the entire movement of the plunger in the reservoir.

Here, provision may be made for the monomer liquid to be sucked from the fluid line into the cartridge interior by means of a reduced pressure in the cartridge interior.

In this way, the reduced pressure generated in the cartridge also serves to move the monomer liquid out of the reservoir in addition to the pressure applied by the expression means. The reduced pressure in the cartridge interior has accumulated during the plunger movement, and this reduced pressure may have caused the monomer liquid to be drawn into the cartridge interior.

It can furthermore be provided that the monomer liquid is introduced into the reservoir before step a), in particular after the monomer liquid container has been opened in the container of the storage and mixing device.

In this way, the method becomes usable for fully prepackaged systems, since the monomer liquid can also be stored for a longer time in the storage and mixing device, in a dedicated monomer liquid container, such as a glass ampoule or a metalized foil bag.

It may furthermore be provided that in step a) the plunger is pushed in the direction of the cartridge backside by means of a mixing rod, wherein the mixing rod is movably supported in an airtight feed-through in the cartridge head, in particular in the delivery opening, and that in step c) the monomer liquid is mixed with the first precursor component by moving the mixing rod and thus the mixing device connected to the mixing rod, moving the mixing device in the cartridge interior between the plunger and the cartridge head.

In this way, the presence of the mixing rod for moving the mixing means in the interior of the cartridge is also used to move the plunger and thus the expression means and to generate a reduced pressure in the interior of the cartridge. Particularly preferably, this mixing rod can be designed as a tube and thus also serve as a delivery conduit for applying the mixed bone cement paste.

Here, provision can also be made for the mixing device to be pulled towards the cartridge head and for the core material to be removed from the mixing rod between steps c) and d) by means of the mixing rod, so that the mixing rod without core material forms a delivery duct through which the mixed bone cement paste is pressed out of the cartridge interior in step d).

In this way, the mixing rod also becomes available as a delivery conduit, and the delivery opening can be used to pass the mixing rod therethrough.

A further development of the method of the invention may provide that, prior to step d), the cartridge is separated from the storage and mixing device and inserted into an extrusion device, by means of which a plunger is pushed in the direction of the cartridge head in step d) using a tappet or an advanceable rod, in order to expel the bone cement paste from the interior of the cartridge.

In this manner, the cartridge may be used separately from the storage and mixing device to apply the ready-mixed bone cement paste. This facilitates handling during application.

It can further be provided that the reservoir is a hollow cylinder and the expression means is a pump plunger which is arranged so as to be movable in the longitudinal direction in the hollow cylinder, wherein the pump plunger is moved in the hollow cylinder by applying pressure with the plunger or is moved pneumatically or hydraulically by means of an overpressure or pressure which is generated in the interior between the rear side of the cartridge and the plunger, wherein preferably the overpressure is passed into the hollow cylinder by means of a compressed gas line or the pressure is passed into the hollow cylinder by means of a hydraulic line.

In this way, the force required to move the pump plunger is obtained from the movement of the plunger in the cartridge in a simple manner. This means that it is sufficient to actuate the plunger to perform a number of different processes in the storage and mixing device.

It can also be provided that the monomer liquid container, in particular a glass ampoule or a foil bag, is opened in the storage and mixing device before steps a) and b), wherein the monomer liquid flows out of the monomer liquid container and into the receptacle, preferably through a screen and/or a filter.

According to the invention, provision can also be made for the cartridge head to be closed to be gas-tight before step a). This ensures that a reduced pressure can be generated in the cartridge interior, at which reduced pressure the parent components can be mixed and, if desired, also available for suction in the monomer liquid. At the same time, however, the cartridge interior may first be sterilized by means of an open cartridge head with the aid of a sterilizing gas (e.g. ethylene oxide).

In theory, the storage and mixing device of the present invention and the method of the present invention may also be implemented using a plurality of cartridges, in each of which a movable plunger is arranged. Said solution is considered to be within the scope of the present invention, since also herein only one cartridge is individually operated or operable according to the present invention.

The present invention is based on the surprising recognition that: the plunger, which is also used for delivering the mixed bone cement paste from the cartridge, can be used first for actuating an expression device, by means of which the monomer liquid can be pressed from the reservoir into the cartridge interior, where it is to be mixed with the bone cement. Furthermore, it has surprisingly been found that the same plunger can be used for generating a reduced pressure and thus for pumping in the monomer liquid. Additional structural elements can be avoided here if a mixing rod is also used to operate or move the plunger to generate the reduced pressure. In addition, the mixing rod may also serve as a delivery conduit to minimize the number of structural elements required. Here, the idea is that the plunger is initially not placed against the backside of the cartridge interior, but is spaced therefrom. The stroke of the plunger to the rear side of the cartridge interior can then be used to actuate an extrusion device, by means of which the monomer liquid can be pressed into the cartridge interior and a reduced pressure can be generated in the cartridge interior, which can be used to mix the bone cement without or with very few air bubbles and by means of which the monomer liquid can be sucked into the cartridge interior. The parent components can therefore be mixed together under reduced pressure using the remaining reduced pressure so that as little gas or air inclusions as possible will be formed in the bone cement paste being produced.

The first storage and mixing device for polymethylmethacrylate bone cement of the invention is for example composed of:

a) a cylindrical cartridge having a cylindrical shape and a cylindrical shape,

b) a plunger axially movable in the cylindrical cartridge,

c) a cartridge head having a feed-through for a mixing rod,

d) a mixing rod axially displaceable through the feed-through of the cartridge head,

e) a mixing device connected to the end of a mixing rod arranged in the interior of the cartridge,

f) an actuating member arranged at an outer end of the mixing rod,

g) at least one monomer liquid container arranged outside the cartridge,

h) an opening device for a monomer liquid container,

i) wherein at least one monomer liquid container is connected in a liquid-permeable manner to the hollow cylinder via an opening, wherein the monomer liquid container is arranged above the opening,

j) a fluid line providing a liquid-permeable connection of the hollow cylinder with the cavity formed by the cartridge, the cartridge head and the plunger at the closed base of the hollow cylinder,

k) a cement powder arranged in a cavity formed by the cartridge, the cartridge head and the plunger,

l) wherein the hollow cylinder is closed by a lid on the upper side, which lid is connected in a gas-permeable manner to the cartridge holder by means of a compressed gas line,

m) wherein an axially movable pump plunger is arranged in the hollow cylinder above the opening in the hollow cylinder, and wherein the cartridge is connected to the cartridge holder in a detachable and airtight manner.

Another alternative storage and mixing device for polymethylmethacrylate bone cement of the invention is for example composed of:

a) a cylindrical cartridge having a cylindrical shape and a cylindrical shape,

b) a plunger axially movable in the cylindrical cartridge,

c) a cartridge head having a feed-through for a mixing rod,

f) an actuating member arranged at an outer end of the mixing rod,

g) at least one monomer liquid container arranged outside the cartridge,

h) an opening device for a monomer liquid container,

i) a cement powder arranged in a cavity formed by the cartridge, the cartridge head and the plunger,

j) wherein an annular cartridge carrier is arranged in the foot below the cartridge, wherein the cartridge is detachably connected to the cartridge carrier,

k) a hollow cylinder arranged below the cartridge holder, wherein at least one monomer liquid container is connected to the hollow cylinder in a liquid-permeable manner through an opening, and wherein the monomer liquid container is arranged above the opening,

l) in which the hollow cylinder is closed off on the underside by a base, the bottom of which is connected in a liquid-permeable manner to a fluid line,

m) wherein an axially movable pump plunger is arranged in the hollow cylinder above the opening in the hollow cylinder, and

n) wherein a cylindrical body is arranged on the upper side of the pump plunger, the outer diameter of said body being smaller than or equal to the inner diameter of the cartridge, wherein the pump plunger with the cylindrical body is arranged in the hollow cylinder in such a way that the upper end of the cylindrical body protrudes inside the cartridge.

Here, it may preferably be provided that the plunger is arranged axially in the cartridge in such a way that the volume of the displacement space formed by the cartridge, the cartridge base and the plunger is equal to or greater than the total volume of the fluid line and the at least one monomer liquid container.

The feed-through for the mixing rod is realized by a delivery opening or is referred to as such herein when using the mixing rod as a delivery conduit. The actuating member may for example be a handle by means of which the mixing rod can be manually operated.

According to the invention, a foot may be provided, to which the cartridge is detachably connected and which is permanently connected to the at least one monomer liquid container.

It may further be provided that a porous disc is arranged in the cartridge head, said disc being permeable to gases and liquids and being connected to the gas-permeable feed-through and closing the cavity, thereby allowing the passage of gases and liquids and not solid particles.

An opening may be arranged in the cartridge head above the porous disc, the opening being closable to be gas tight and having at least 20mm²Area and connected to the surrounding atmosphere.

According to the invention, it can furthermore be provided that the plunger has at least one catch element which can be detachably engaged with a complementary catch element on the cartridge inner side above the cartridge base.

The invention includes, for example, methods of mixing and delivering polymethylmethacrylate bone cement. The method is characterized by the following sequential steps:

a) the head of the medicine barrel is sealed to be airtight,

b) at least one of the monomer liquid containers is opened,

c) the monomer liquid is caused to flow from the monomer liquid container into the hollow cylinder through the opening,

d) the actuating member of the mixing rod is pushed in the direction of the cartridge base (the back side of the cartridge interior),

e) the plunger is displaced in the direction of the cartridge base by means of the mixing rod,

f) a reduced pressure is generated in the cavity formed by the cartridge, the cartridge head and the plunger (in the cartridge interior),

g) an overpressure is created in the cavity (in the cartridge interior) formed by the cartridge, the closed back side of the cartridge and the plunger,

h) an overpressure is passed through the pressure line over the axially displaceable pump plunger in the hollow cylinder,

i) the pump plunger is moved in the direction of the base of the hollow cylinder,

j) due to the generated reduced pressure and pressing it out of the hollow cylinder by means of a pump plunger moving in the direction of the base, monomer liquid is transferred from the hollow cylinder into the cartridge interior via the fluid line,

k) mixing the cement powder with the monomer liquid by manually actuating the actuating element of the mixing rod by axial and rotational movement of the mixing device,

l) the mixing rod is pulled towards the cartridge head,

m) removing the core material from the hollow mixing rod,

n) inserting the cartridge into the expression means,

o) actuating the expression device, wherein the plunger is moved in the direction of the cartridge head, and

p) pressing the mixed bone cement paste out of the cartridge through a hollow mixing rod.

The method is designed to utilize the aforementioned first storage and mixing device of the present invention and reflect its manner of operation.

The present invention also includes alternative methods such as mixing and delivering polymethylmethacrylate bone cement. The alternative method is characterized by the following sequential steps:

a) the head of the medicine barrel is sealed to be airtight,

b) at least one of the monomer liquid containers is opened,

g) the cylindrical body of the pump plunger is displaced by axially displacing the plunger in the cartridge backside direction,

h) by means of the reduced pressure generated and pressing it out of the hollow cylinder by means of a pump plunger moving in the direction of the base, monomer liquid is transferred from the hollow cylinder to the interior of the cartridge via the fluid line,

i) mixing the cement powder with the monomer liquid by manually actuating the actuating element of the mixing rod, by axial and rotational movement of the mixing device,

j) the mixing rod is pulled towards the cartridge head,

k) the core material is removed from the hollow mixing rod,

l) inserting the cartridge into an expression device,

m) actuating the expression device, wherein the plunger is moved in the direction of the cartridge head, and

n) pressing the mixed bone cement paste out of the cartridge through a hollow mixing rod.

An alternative method is designed to take advantage of and reflect the manner in which the aforementioned alternative storage and mixing devices of the present invention operate.

Drawings

Further embodiments of the invention will be explained below with reference to 13 schematic drawings, but the invention is by no means limited thereto. The drawings show that:

FIG. 1: a schematic cross-sectional view of a first exemplary storage and mixing device of the present invention in an initial state;

FIG. 2: a schematic perspective view of the storage and mixing device according to figure 1;

FIG. 3: a schematic cross-sectional view of a first exemplary storage and mixing device, wherein the monomer liquid container has been opened;

FIG. 4: a schematic cross-sectional view of the first exemplary storage and mixing device while or after the monomer liquid has been pressed in;

FIG. 5: a schematic, partial cross-sectional view of a first exemplary storage and mixing device, wherein the bone cement paste has been mixed;

FIG. 6: a schematic cross-sectional view of a lower portion of a first exemplary storage and mixing device, wherein the cross-sectional plane is perpendicular to the cross-sectional planes in fig. 1, 3, 4, and 5;

FIG. 7: a schematic cross-sectional view of a second exemplary storage and mixing device of the present invention in an initial state;

FIG. 8: a schematic perspective view of a second exemplary storage and mixing device according to fig. 7;

FIG. 9: a schematic cross-sectional view of a second exemplary storage and mixing device, wherein the monomer liquid container has been opened;

FIG. 10: a schematic cross-sectional view of a second exemplary storage and mixing device as monomer liquid is being forced in;

FIG. 11: a schematic cross-sectional view of the second exemplary storage and mixing device after the monomer liquid has been pressed in;

FIG. 12: a schematic, partial cross-sectional view of a second exemplary storage and mixing device, wherein the bone cement paste has been mixed; and is

FIG. 13: two enlarged sections of the upper region of the second storage and mixing device of the invention, a schematic perspective view on the left and a schematic partial sectional view on the right.

Detailed Description

Fig. 1 to 6 show an exemplary embodiment of a first storage and mixing device of the present invention. Here, fig. 1 shows a schematic cross-sectional view of a first exemplary storage and mixing device of the present invention in an initial state. The storage and mixing device comprises a cartridge 1 having a cylindrical interior, wherein a plunger 2 is arranged to be linearly movable in an axial direction. On the front side of the cartridge 1 (fig. 1 and 3 to 5, at the top), the interior or cartridge 1 is closed by a cartridge head 3 similar to a cap or cap. The cartridge head 3 is sealed against the cartridge 1 by means of a circumferential seal. In the interior of the cartridge 1, bone cement powder 4, which is the first matrix component 4 of PMMA bone cement, is located between the plunger 2 and the cartridge head 3.

The plunger 2 is in airtight contact with the inner wall of the interior of the cartridge 1 by means of a circumferential rubber seal. In this way, movement of the plunger 2 away from the cartridge head 3 may cause a reduced pressure to be generated in the interior of the cartridge 1, said reduced pressure being vented through the feed-through 5 in the cartridge head 3 onto the fluid line 6 or acting on the fluid line 6.

A container 7 separate from the cartridge 1 is arranged close to the cartridge 1. The glass ampoule 8 is inserted upside down into the container 7. The glass ampoule 8 is not shown in the cross-section of the cross-sectional views of fig. 1 and 3 to 5, and is filled with the monomer liquid 42 (see fig. 3 and 4) in fig. 1.

A central delivery opening is located in the cartridge head 3 and a hollow or tubular mixing rod 9 passes therethrough. The hollow mixing rod 9 is closed on the inside by means of a core material 10 which can be pulled out of the mixing rod 9. In the region of the delivery opening, the mixing rod 9 is sealed against the cartridge head 3 by means of a circumferential seal, so that even when the mixing rod 9 rotates and moves in the longitudinal direction in the delivery opening, the reduced pressure in the interior of the cartridge 1 cannot (or at least cannot be so fast) draw air between the cartridge head 3 and the mixing rod 9 into the interior of the cartridge 1.

A handle 12 is arranged on the front end of the mixing rod 9, by means of which handle the mixing rod 9 is manually movable in the longitudinal direction relative to the cartridge 1 and is axially rotatable. In addition, the handle 12 can be used to pull the core 10 out of the mixing rod 9 after the locking mechanism (not shown) has been removed or the resistance has been overcome.

A mixing device 14 with a plurality of mixing blades 14 is attached to the mixing rod 9 between the plunger 2 and the cartridge head 3 in the interior of the cartridge 1 such that the mixing device 14 will rotate and move axially in the interior of the cartridge 1 when the mixing rod 9 rotates and moves relative to the cartridge 1. In this way, the contents in the interior of the cartridge 1 can be mechanically mixed with the aid of the mixing device 14 by means of the mixing rod 9.

The pump plunger 15 is inserted into the back side of the cartridge 1 and has a cylindrical attachment as an extension on its front side that protrudes below the plunger 2 in the interior of the cartridge 1, but is spaced from the plunger 2 in its initial position (see fig. 1). The pump plunger 15 is supported to be movable in the longitudinal direction in the cylindrical reservoir 16 and is sealed against the inner wall of the cylindrical reservoir 16 by means of two circumferential seals 46 (see fig. 6). For this purpose, the reservoir 16 is arranged adjacent to and below the cartridge 1. The fluid line 6 leads into the reservoir 16 on the underside of the reservoir 16.

The fluid line 6 extends in some areas parallel to the axis of the cylindrical cartridge 1 downwards away from the cartridge head 3, then curves and continues upwards to the mouth leading into the reservoir 16. The reservoir 16 may also be considered a widened portion of the fluid line 6. Reservoir 16 forms a reservoir for monomer liquid 42 from glass ampoule 8.

To generate a reduced pressure in the interior of the cartridge 1, the plunger 2 is movable in the back direction of the cartridge 1 (in fig. 1 to 6 at the bottom, i.e. downwards) or in the back direction of the interior of the cartridge 1 by manually pushing the plunger 2 in the back direction with the aid of the mixing rod 9. In order that the plunger 2 is not pushed out of the interior of the cartridge 1 at the bottom, a stop 18 in the form of a circumferential flange is provided on the inside of the cartridge 1 in the rear region of the interior. Thus, in the direction of the back side of the cartridge 1, the plunger 2 can only be pushed as far as the stop 18. However, its movement has been blocked earlier by the pump plunger 15 when it reaches the base of the reservoir 16. However, the stop 18 ensures that the plunger 2 does not exit through the back side of the cartridge 1 after the cartridge 1 has been removed from the storage and mixing device.

This is because the cartridge 1 is detachably connected to the foot 20. Two circumferential protrusions 22 are arranged on the outside of the backside of the cartridge 1 to attach it to the foot 20. For this purpose, the cartridge 1 engages with the foot 20 at the bottom, i.e. in the rear area, by means of the bracket 23. The aforementioned projections 22 may also be used to attach an extrusion device (not shown) by means of which the ready-mixed bone cement paste 44 (see fig. 5) can be applied. For this purpose, the plunger 2 is pushed into the cartridge 1 in the direction of the cartridge head 3 as delivery plunger 2 by means of an extrusion device actuated by an advanceable rod, whereby the bone cement paste 44 is extruded through the delivery conduit 9 or hollow mixing rod 9.

The glass ampoule 8 has a rupturable ampoule head 24. When the ampoule head 24 is broken or ruptured, the glass ampoule 8 is opened. The container 7 is made of an elastically deformable material, which is thickened at the neck between the ampoule head 24 and the body of the ampoule 8. In this way, the ampoule head 24 is safely supported while the body of the ampoule 8 can move due to the elasticity of the insert forming the receptacle 7. The glass ampoule 8 can thus be broken open in the storage and mixing device. On the back side of the container 7, a plug 26 is provided as a cover 26, by means of which the glass ampoule 8 is held in place. The lid 26 is provided with two openings through which air can flow into the interior of the container 7.

A filter 28 and/or a screen 28 is arranged in the connection between the container 7 and the receptacle 16 or below the container 7, which blocks shards or glass fragments of the glass ampoule 8 that may be produced when the glass ampoule 8 is broken open. Below the filter 28 and/or the screen 28, the base is inclined and the container 7 and the receptacle 16 are connected to each other in a liquid-permeable manner through the opening 30. After the glass ampoule 8 has been opened, the monomer liquid 42 flows downward, over the sloped surface and through the opening 30, into the receptacle 16 (see fig. 3). Here, the broken ampoule head 24 and any glass debris generated are retained by the screen 28 and/or filter 28.

A fitting 32 with an external thread is provided in the region of the delivery opening on the cartridge head 3. A conical collet nut 34 can be screwed onto this external thread as a fastening means 34 to fix the mixing rod 9 relative to the cartridge head 3. To enable fixing of the mixing rod 9 relative to the cartridge head 3, a collet nut 34 is further screwed onto the external thread of the adapter 32. To initially prevent this fixing or to avoid unintentional fixing, extractable fixing means (not shown) in the form of buckles with gripping tabs may be provided, arranged between the sleeve nut 34 and the cartridge head 3. Upon pulling out the fixation device, the collet nut 34 may be further screwed onto the external thread of the fitting 32, such that the fitting 32 is compressed, thereby fixing the mixing rod 9 relative to the cartridge head 3.

An additional lateral opening is provided in the cartridge head 3 through which a sterilizing gas (e.g. ethylene oxide) can pass to the interior of the cartridge 1. As shown, the lateral opening is closed by means of a closure 40.

A porous disc 36 or a porous filter 36 is arranged between the cartridge head 3 and the interior of the cartridge 1, said disc or filter being permeable to gases and liquids but impermeable to powders and solid materials, such as bone cement powder 4, so that the feed-through 5 is connected to the remaining interior of the cartridge 1 only through the porous filter 36. The porous filter 36 prevents the bone cement powder 4 from entering the fluid line 6 and thus prevents inadvertent premature reaction of the bone cement powder 4 with the monomer liquid 42 and thus prevents inadvertent blocking of the thinner portion of the fluid line 6.

Fig. 1 to 6 are used to describe in the following an exemplary method of the invention, which is carried out using the storage and mixing device of the invention. A fully assembled storage and mixing device is provided as shown in fig. 1 and 2. The glass ampoule 8 is opened by breaking off the ampoule head 24, so that the monomer liquid 42 flows out of the glass ampoule 8, through the filter 28 and/or the screen 28 and the opening 30, into the receptacle 16 and into the lower region of the fluid line 6. Here, the glass fragments and the broken ampoule head 24 are retained by the screen 28 and/or the filter 28. Monomer liquid 42 from glass ampoule 8 is now filled into reservoir 16 and fluid line 6 and ready for use. This situation is shown in fig. 3.

To generate a reduced pressure in the interior of the cartridge 1 to avoid gas inclusions in the bone cement paste 44 (see fig. 6) and to transfer the monomer liquid 42 into the interior of the cartridge 1, the plunger 2 is pushed in the dorsal direction of the cartridge 1 with the aid of the mixing rod 9. Thus, the volume between the plunger 2 and the cartridge head 3 is expanded in the interior of the cartridge 1, so that a reduced pressure is generated. The gas between the plunger 2 and the pump plunger 15 can escape to the outside, so that no overpressure builds up between the plunger 2 and the pump plunger 15. The plunger 2, after having covered the distance between the plunger 2 and the pump plunger 15, meets the pump plunger 15 and pushes the pump plunger 15 towards the mouth of the fluid line 6 leading into the reservoir 16. Here, the opening 30 closes and presses the monomer liquid 42 from the reservoir 16 into the fluid line 6 and subsequently through the fluid line 6 and the feed-through 5 into the interior of the cartridge 1 between the plunger 2 and the cartridge head 3. In addition, the reduced pressure draws monomer liquid 42 from fluid line 6 into cartridge 1 and ultimately through feed-through 5 and porous filter 30 into cartridge 1 (see fig. 4). At the beginning (see fig. 1), the plunger 2 is spaced from the back side or stop 18 to such an extent that the total travel of the plunger 2 to the stop 18 is sufficient to reduce the pressure between the plunger 2 and the cartridge head 3 in the interior of the cartridge 1 by at least half. The pump plunger 15 is pushed into the reservoir 16 as far as the stopper to force all of the monomer liquid 42 out of the reservoir 16. A residual amount of monomer liquid 42 remains in fluid line 6.

When the monomer liquid 42 has been pressed into the interior of the cartridge 1 by means of the pump plunger 15, it can be mixed with the bone cement powder 4 with the aid of the mixing device 14 by axially moving the mixing device 14 in the longitudinal direction with the aid of the mixing rod 9 and manually rotating it in the interior of the cartridge 1. In this manner, a ready-mixed bone cement paste 44 (see fig. 6) is produced. The mixing device 14 is then pulled with the aid of the mixing rod 9 as far as the stop towards the cartridge head 3, removing any fixing means (not shown) present and fixing the mixing rod 9 relative to the cartridge head 3 by means of the collet nut 34. The core material 10 is pulled out of the mixing rod 9 with the aid of a handle 12. The mixing rod 9 now forms a delivery conduit 9 which is arranged in or through the delivery opening and through which the ready-mixed bone cement paste 44 can be applied.

For this purpose, the cartridge 1 is separated from the foot 20 by pulling the cartridge 1 out and pulling the fluid line 6 away from the feed-through 5. A one-way valve (not shown) may be provided in fluid line 6 to prevent residual monomer liquid 42 from exiting fluid line 6. The cartridge 1 is then inserted into an extrusion device (not shown) by means of which the plunger 2 can be pushed in the direction of the cartridge head 3 with the aid of an advanceable rod as a delivery plunger 2. In this way, the bone cement paste 44 is pressed out through the delivery conduit 9 and through the delivery opening. No bone cement paste 44 can escape through the feed-through 5 because the porous filter 36 blocks the bone cement paste 44.

Fig. 7 through 13 show an exemplary embodiment of an alternative second storage and mixing device of the present invention. Here, fig. 7 shows a schematic cross-sectional view of a first exemplary storage and mixing device of the present invention in an initial state. The storage and mixing device comprises a cartridge 51 having a cylindrical interior, wherein a plunger 52 is arranged to move linearly in an axial direction. On the front side of the cartridge 51 (fig. 7 and 9 to 13, at the top), the interior or cartridge 51 is closed by a cartridge head 53 similar to a cap or cap. The cartridge head 53 is sealed against the cartridge 51 by means of a circumferential seal. In the interior of the cartridge 51, bone cement powder 54, which is a first matrix component 54 of PMMA bone cement, is located between the plunger 52 and the cartridge head 53.

The plunger 52 is in airtight contact with the inner wall of the interior of the cartridge 51 by means of a circumferential rubber seal. In this way, a movement of the plunger 52 away from the cartridge head 53 may cause a reduced pressure to form in the interior of the cartridge 51 between the plunger 52 and the cartridge head 53, said reduced pressure being passed through the feed-through 55 in the cartridge head 53 onto the fluid line 56 or acting on the fluid line 56 and causing an overpressure to be generated between the plunger 52 and the closure on the rear side of the cartridge 51 or causing a pressure to be exerted on the hydraulic liquid (not shown) contained therein.

A container 57 separate from the cartridge 51 is arranged adjacent to the cartridge 51. The glass ampoule 58 is inserted upside down into the container 57. The glass ampoule 58 is not shown in the cross-sectional views of fig. 7 and 9 to 12 in section, and is filled with the monomer liquid 92 (see fig. 9 to 11) in fig. 7.

A central delivery opening is located in the cartridge head 53 and a hollow or tubular mixing rod 59 passes therethrough. The hollow mixing rod 59 is closed on the inside by a core material 60 which can be pulled out of the mixing rod 59. In the region of the delivery opening, the mixing rod 59 is sealed against the cartridge head 53 by means of a circumferential seal, so that even when the mixing rod 59 rotates and moves in the longitudinal direction in the delivery opening, the reduced pressure in the interior of the cartridge 51 cannot (or at least cannot be so quickly) draw air between the cartridge head 53 and the mixing rod 59 into the interior of the cartridge 51.

A handle 62 is arranged on the front end of the mixing rod 59, by means of which handle the mixing rod 59 is manually movable in longitudinal direction with respect to the cartridge 51 and is axially rotatable. In addition, handle 62 may be used to pull core 60 out of mixing rod 59 after a locking mechanism (not shown) has been removed or resistance has been overcome.

A mixing device 64 having a plurality of mixing blades 64 is attached to the mixing rod 59 between the plunger 52 and the cartridge head 53 in the interior of the cartridge 51 such that when the mixing rod 59 rotates and moves relative to the cartridge 51, the mixing device 64 will rotate and move axially in the interior of the cartridge 51. In this way, the contents in the interior of the cartridge 51 can be mechanically mixed with the aid of the mixing device 64 by means of the mixing rod 59.

The pump plunger 65 is disposed in a hollow cylinder 67 above the reservoir 66. A hollow cylinder 67 is arranged close to the cartridge 51 and delimits the reservoir 66 laterally and at the bottom, wherein the pump plunger 65 delimits the reservoir 66 at the top. In order that the plunger 52 is not pushed out of the interior of the cartridge 51 at the bottom, a stop 68 in the form of a circumferential flange is provided on the inside of the cartridge 51 in the rear region of the interior. Thus, in the direction of the back side of the cartridge 51, the plunger 52 may only be pushed as far as the stop 68. The stop 68 ensures that the plunger 52 does not exit through the back side of the cartridge 51 after the cartridge 51 has been removed from the storage and mixing device.

The back side of the cartridge 51 is closed with a pressure seal and a gas line 69 or hydraulic line 69 is connected to the base of the closure and connects the back side of the cartridge 51 to the upper side of the hollow cylinder 67. The pump plunger 65 is in pressure-tight contact with the inner wall of the hollow cylinder 67 with the aid of 3 circumferential seals. The pump plunger 65 is supported to be movable in the longitudinal direction in a cylindrical cavity formed by the hollow cylinder 67. The fluid line 56 leads into the reservoir 66 on the underside of the reservoir 66.

The fluid line 56 extends in some areas parallel to the axis of the cylindrical cartridge 51, downward away from the cartridge head 53, then curves and continues upward to a mouth leading into a reservoir 66. The reservoir 66 may also be considered a widened portion of the fluid line 56. Reservoir 66 forms a reservoir for monomer liquid 92 from glass ampoule 58.

In order to generate a reduced pressure in the interior of the cartridge 51, the plunger 52 can be moved in the back direction of the cartridge 51 (in fig. 7 to 12, at the bottom, i.e. downwards) or in the back direction of the interior of the cartridge 51 by manually pushing the plunger 52 in the back direction with the aid of the mixing rod 59.

The cartridge 51 is removably attached to the foot 70. Two circumferential protrusions 72 are arranged on the outside of the backside of the cartridge 51 to attach it to the foot 70. For this purpose, the cartridge 51 engages with the foot 70 at the bottom, i.e. in the rear region, by means of a bracket 73. The aforementioned projections 72 may also be used to attach an extrusion device (not shown) by means of which a ready-mixed bone cement paste 94 (see fig. 12) may be applied. For this purpose, the plunger 52 is pushed into the cartridge 51 in the direction of the cartridge head 53 as delivery plunger 52 by means of an extrusion device actuated by an advanceable rod, whereby the bone cement paste 94 is extruded through the delivery conduit 59 or hollow mixing rod 59.

The glass ampoule 58 has a rupturable ampoule head 74. When the ampoule head 74 is broken or ruptured, the glass ampoule 58 is opened. The container 57 is made of a resiliently deformable material which is thickened at its neck between the ampoule head 74 and the body of the ampoule 58. In this way, the ampoule head 74 is safely supported whilst the body of the ampoule 58 can move due to the resilience of the insert forming the receptacle 57. Thus, the glass ampoule 58 may be broken within the storage and mixing device. On the back side of the container 57, a plug 76 is provided as a cover 76, by means of which the glass ampoule 58 is held in place. The lid 76 is provided with two openings (see fig. 8) through which air can flow into the interior of the container 57.

A filter 78 and/or a screen 78 is disposed in the connection between the container 57 and the receptacle 66 or below the container 57, which blocks shards or glass chips of the glass ampoule 58 that may be generated when the glass ampoule 58 is broken open. Below the filter 78 and/or screen 78, the base is inclined and the container 57 and receptacle 66 are connected to each other in a liquid-permeable manner through an opening 80. After the glass ampoule 58 has been opened, the monomer liquid 92 flows downward, over the sloped surface and through the opening 80 into the reservoir 66 (see fig. 9). Here, the broken ampoule head 74 and any glass debris generated are retained by the screen 78 and/or filter 78.

A fitting 82 with an external thread is provided on the cartridge head 53 in the region of the delivery opening. A tapered collet nut 84 may be screwed onto this external thread as a fastening means 84 to secure the mixing rod 59 relative to the cartridge head 53. To secure the mixing rod 59 relative to the cartridge head 53, a collet nut 84 is further screwed onto the external threads of the adapter 82. To initially prevent this fixation or to avoid unintentional fixation, extractable fixation means (not shown) in the form of buckles with gripping tabs may be provided, arranged between the sleeve nut 84 and the cartridge head 53. Upon pulling out the fixture, a collet nut 84 may be further screwed onto the external threads of the fitting 82, causing the fitting 82 to compress, thereby securing the mixing rod 59 relative to the cartridge head 53.

An additional lateral opening is provided in the cartridge head 53 through which a sterilizing gas (e.g. ethylene oxide) can pass to the interior of the cartridge 51. As shown, the lateral opening is closed by means of a closure 90. The closure 90 is shown in an open position in fig. 13. In the open position according to fig. 13, the interior of the cartridge 51 can be sterilized by introducing a sterilizing gas (e.g. ethylene oxide) through an opening arranged laterally close to the delivery opening in the cartridge head 53. Subsequently, the closure 40 can be pushed into the opening to close the opening. The collet nut 84 is then screwed onto the fitting 82 to such an extent that the mixing rod 59 seals against the cartridge head 53, but is still free to move within the delivery opening.

A porous disc 86 or porous filter 86 is arranged between the cartridge head 53 and the interior of the cartridge 51, said disc or filter being permeable to gases and liquids but impermeable to powders and solid materials, such as bone cement powder 54, so that the feed-through 55 is connected to the remaining interior of the cartridge 51 only through the porous filter 86. The porous filter 86 prevents the bone cement powder 54 from entering the fluid line 56 and thus prevents inadvertent premature reaction of the bone cement powder 54 with the monomer liquid 92 and thus prevents inadvertent blocking of the thinner portion of the fluid line 56.

Fig. 7-12 are used to hereinafter describe exemplary methods of the invention, which are implemented using the storage and mixing apparatus of the invention. A fully assembled storage and mixing device is provided as shown in fig. 7 and 8. The glass ampoule 58 is opened by breaking off the ampoule head 74, so that the monomer liquid 92 flows out of the glass ampoule 58, through the filter 78 and/or the screen 78 and the opening 80, into the reservoir 66 and into the lower region of the fluid line 56. Here, the glass fragments and broken ampoule head 74 are retained by the screen 78 and/or filter 78. Monomer liquid 92 from glass ampoule 58 is now filled into reservoir 66 and fluid line 56 and ready for use. This situation is shown in fig. 9.

In order to generate a reduced pressure in the interior of the cartridge 51 to avoid gas inclusions in the bone cement paste 94 (see fig. 12) and to transfer the monomer liquid 92 into the interior of the cartridge 51, the plunger 52 is pushed in the dorsal direction of the cartridge 51 with the aid of the mixing rod 59. Thus, the volume in the interior of the cartridge 51 between the plunger 52 and the cartridge head 53 is expanded, so that a reduced pressure is generated. At the same time, an overpressure is generated between the plunger 52 and the closed back side of the cartridge 51, which overpressure is introduced into the hollow cylinder 67 through the gas line 69, either with the top between the upper side of the hollow cylinder 67 and the pump plunger 65, or a hydrostatic pressure is generated, which is passed through the hydraulic line 69 into the hollow cylinder 67 with the top between the upper side of the hollow cylinder 67 and the pump plunger 65. The overpressure or hydrostatic pressure causes the pump plunger 65 in the hollow cylinder 67 to push down towards the mouth of the fluid line 56 leading into the reservoir 66. Here, the opening 80 closes and presses the monomer liquid 92 from the reservoir 66 into the fluid line 56 and subsequently through the fluid line 56 and the feed-through 55 into the interior of the cartridge 51 between the plunger 52 and the cartridge head 53. In addition, the reduced pressure draws the monomer liquid 92 from the fluid line 56 into the cartridge 51 and ultimately through the feed-through 55 and the porous filter 80 into the cartridge 51 (see fig. 10 and 11). At the beginning of the movement (see fig. 7), the plunger 52 is spaced from the back side or stop 68 to such an extent that the total stroke of the plunger 52 to the stop 68 is sufficient to reduce the pressure (gas pressure) between the plunger 52 and the cartridge head 53 in the interior of the cartridge 51 by at least half and to allow an overpressure to build up between the plunger 52 and the closed back side of the cartridge 51 sufficient to exert pressure on the pump plunger 65 in the hollow cylinder 67, or to a volume equal to the volume of the stroke of the pump plunger 65.

Since the space between the plunger 52 and the closed back side of the cartridge 51, in the gas line 69 or hydraulic line 69, and between the pump plunger 65 and the upper side of the hollow cylinder 67 is closed, it can be provided that hydraulic fluid (not shown) is provided in this closed space, by means of which pressure can be transferred hydraulically through the hydraulic line 69.

The pump plunger 65 is pushed into the reservoir 66 as far as the stop to force all of the monomer liquid 92 out of the reservoir 66. A residual amount of monomer liquid 92 remains in fluid line 56.

When the monomer liquid 92 has been pressed into the interior of the cartridge 51 by means of the pump plunger 65, it can be mixed with the bone cement powder 54 with the aid of the mixing device 64 by axially moving the mixing device 54 in the longitudinal direction with the aid of the mixing rod 59 and manually rotating it in the interior of the cartridge 51. In this manner, a ready-mixed bone cement paste 94 (see fig. 12) is produced. The mixing device 64 is then pulled with the aid of the mixing rod 59 as far as the stop towards the cartridge head 53, removing any securing means (not shown) present and securing the mixing rod 59 relative to the cartridge head 53 by means of the collet nut 84. The core material 60 is pulled out of the mixing rod 59 with the aid of a handle 62. The mixing rod 59 now forms a delivery conduit 59 that is disposed in or through the delivery opening and through which the ready-mixed bone cement paste 94 can be applied.

For this purpose, the cartridge 51 is separated from the foot 70 by pulling the cartridge 51 out and pulling the fluid line 56 away from the feed-through 55. A one-way valve (not shown) may be provided in the fluid line to prevent residual monomer liquid 92 from exiting the fluid line 56. The cartridge 51 is then inserted into an expression device (not shown) by means of which the plunger 52 can be pushed in the direction of the cartridge head 53 as a delivery plunger 52 with the aid of an advanceable rod. In this manner, the bone cement paste 94 is expressed through the delivery conduit 59 and through the delivery opening. The bone cement paste 94 cannot escape through the feed-through 55 because the porous filter 86 retains the bone cement paste 94.

The features of the invention disclosed in the above description, the claims, the drawings and the exemplary embodiments may be relevant both individually and in combination for implementing different embodiments of the invention.

List of reference numbers

1. 51 Cartridge

2. 52 plunger/delivery plunger

3. 53 medicine cylinder head

4. 54 bone cement powder/first matrix component

5. 55 feed-through device

6. 56 fluid line

7. 57 container

8. 68 monomer liquid container/glass ampoule

9. 59 mixing rod/delivery tube

10. 60 core material

12. 62 handle

14. 64 mixing blade/mixing device

15. 65 pump plunger

16. 66 reservoir

18. 68 stop

20. 70 foot

22. 72 projection

23. 73 bracket

24. 74 ampoule head

26. 76 cap/plug

28. 78 mesh/filter

30. 80 opening

32. 82 fitting with external threads

34. 84 taper sleeve nut/fastener arrangement

36. 86 porous filter/porous disc

40. 90 closure

42. 92 monomer liquid

44. 94 Mixed bone cement paste

46 seal

67 hollow cylinder

69 gas/hydraulic line

Claims

1. A storage and mixing device for a two-component polymethylmethacrylate bone cement having

A cartridge (1, 51) having a cylindrical interior, wherein the cylindrical interior is delimited on a front side by a cartridge head (3, 53) having a closed delivery opening,

a plunger (2, 52) arranged axially movable in the cylindrical interior of the cartridge (1, 51) and spaced from the cartridge head (3, 53), wherein the plunger (2, 52) is placed circumferentially against an inner wall of the interior of the cartridge (1, 51) such that the plunger (2, 52) divides the interior of the cartridge (1, 51) into two sections,

a powdered first parent component (4, 54) of said bone cement contained in said interior of said cartridge (1, 51) between said plunger (2, 52) and said cartridge head (3, 53),

a feed-through device (5, 55) arranged in the cartridge head (3, 53) or in a cylindrical sleeve of the cartridge (1, 51) between the plunger (2, 52) and the cartridge head (3, 53), wherein the feed-through device (5, 55) is connected to a fluid line (6, 56),

a reservoir (16, 66) of a monomer liquid (42, 92), wherein the fluid line (6, 56) connects the feed-through device (5, 55) to the reservoir (16, 66) in a liquid-permeable manner, wherein the monomer liquid (42, 92) as a second parent component of the bone cement is contained in the reservoir (16, 66) or is fillable or introducible into the reservoir (16, 66),

a pressing-out device (15, 65) which can be pushed into the reservoir (16, 66) such that a monomer liquid (42, 92) can be pushed from the reservoir (16, 66) into the fluid line (6, 56),

wherein the plunger (2, 52) is spaced from a back side of the cylindrical interior, which is located opposite the front side, such that by moving the plunger (2, 52) in the direction of the back side, the expression means (15, 65) can be pushed into the reservoir (16, 66) and a reduced pressure can be generated in the interior of the cartridge (1, 51) between the plunger (2, 52) and the cartridge head (3, 53),

a mouth (30, 80) for introducing the monomer liquid (42, 92) into the reservoir (16, 66) is arranged in the region of the expression device (15, 65), wherein the mouth (30, 80) is closed by pushing into the expression device (15, 65) when the expression device (15, 65) starts to move into the reservoir (16, 66).

2. Storage and mixing device according to claim 1, characterized in that

The plunger (2, 52) in the interior of the cartridge (1, 51) can be manually pushed or pulled in the direction of the back side of the interior of the cartridge (1, 51) by means of a rod (9, 59) or another force transmission member.

3. Storage and mixing device according to claim 2, characterized in that

An actuating member or handle (12, 62) for operating the rod (9, 59) or the force transmission member is attached to the rod (9, 59) or the force transmission member.

4. Storage and mixing device according to claim 1 or 2, characterized in that

A filter (36, 86) is arranged in the cartridge head (3, 53), in the feed-through device (5, 55) and/or in the fluid line (6, 56), wherein the filter (36, 86) is permeable to the monomer liquid (42, 92) and impermeable to the powdery first parent component (4, 54).

5. Storage and mixing device according to claim 4, characterized in that

The filter (36, 86) is a porous filter.

6. Storage and mixing device according to claim 1 or 2, characterized in that

The plunger (2, 52) is spaced from a back side of the cylindrical interior at a location opposite the front side to an extent such that the reduced pressure can draw the monomer liquid (42, 92) from the fluid line (6, 56) into the interior of the cartridge (1, 51).

7. Storage and mixing device according to claim 1 or 2, characterized in that

The storage and mixing device has a container (7, 57) which is separate from the cartridge (1, 51) and from the reservoir (16, 66) and which contains the monomer liquid (42, 92) therein, wherein the container (7, 57) is connected to the reservoir (16, 66).

8. Storage and mixing device according to claim 7, characterized in that

A closed monomer liquid container (8, 58) or foil pouch containing the monomer liquid (42, 92) is arranged or arrangeable in the container (7, 57), wherein the monomer liquid container (8, 58) is breakable within the container (7, 57) or the foil pouch is pierceable or tearable within the container (7, 57).

9. Storage and mixing device according to claim 7, characterized in that

The container (7, 57) is connected to the reservoir (16, 66) through the mouth (30, 80).

10. Storage and mixing device according to claim 7, characterized in that

The cartridge (1, 51), the reservoir (16, 66), the container (7, 57) and the fluid line (6, 56) are connected to a common holder (20, 70), wherein the reservoir (16, 66), the container (7, 57) and the fluid line (6, 56) are permanently connected to the holder (20, 70) and the cartridge (1, 51) is detachably connected to the holder (20, 70).

11. Storage and mixing device according to claim 10, characterized in that

The cartridge (1, 51) is screwed to the holder (20, 70) by means of a thread or is connected to the holder (20, 70) by means of a locking mechanism (22, 23, 72, 73).

12. Storage and mixing device according to claim 7, characterized in that

A monomer liquid container (8, 58) is contained in the container (7, 57) that is openable within the container (7, 57) such that the monomer liquid (42, 92) flows from the opened monomer liquid container (8, 58) into the receptacle (16, 66).

13. Storage and mixing apparatus according to claim 12, wherein

An opening device operable from the outside for opening the monomer liquid container (8, 58) is arranged on the container (7, 57).

14. Storage and mixing apparatus according to claim 12, wherein

The monomer liquid container (8, 58) is a foil bag or a glass ampoule.

15. Storage and mixing device according to claim 1 or 2, characterized in that

A mixing device (14, 64) is arranged in the interior of the cartridge (1, 51) between the plunger (2, 52) and the cartridge head (3, 53), by means of which mixing device the first parent component (4, 54) can be mixed with the monomer liquid (42, 92) in the interior of the cartridge (1, 51).

16. Storage and mixing apparatus according to claim 15, wherein

The mixing device (14, 64) is operable from the outside of the cartridge (1, 51) by means of a rod (9, 59), wherein the rod (9, 59) passes through the cartridge head (3, 53) in an air-tight manner and is rotatable and movable in the axial direction.

17. Storage and mixing apparatus according to claim 16, wherein

The rod (9, 59) passes through the delivery opening.

18. Storage and mixing apparatus according to claim 16, wherein

The plunger (2, 52) can be pushed by means of the rod (9, 59) in the direction of the rear side of the interior of the cartridge (1, 51).

19. Storage and mixing apparatus according to claim 16, wherein

The rod (9, 59) is a delivery conduit in which a manually removable core material (10, 60) is arranged such that the mixed bone cement paste (44, 94) can be expelled from the interior of the cartridge (1, 51) through the delivery conduit without the core material (10, 60).

20. Storage and mixing device according to claim 1 or 2, characterized in that

On the inside of the interior of the cartridge (1, 51), a stop (18, 68) is provided on the back side, which limits the movement of the plunger (2, 52) in the direction of the back side.

21. Storage and mixing device according to claim 1 or 2, characterized in that

The plunger (2, 52) has at least one catch element which can be detachably engaged with a complementary catch element on the inside of the cartridge (1, 51) in the region of the rear side of the interior of the cartridge (1, 51).

22. Storage and mixing device according to claim 1 or 2, characterized in that

A gas-permeable opening is arranged in the cartridge head (3, 53), wherein a gas-permeable and solid particle-impermeable porous disc (36, 86) is arranged between the first parent component (4, 54) and the gas-permeable opening.

23. Storage and mixing apparatus according to claim 22, wherein

The porous disc (36, 86) is arranged in the cartridge head (3, 53).

24. Storage and mixing apparatus according to claim 22, wherein

The gas-permeable opening is closable.

25. Storage and mixing device according to claim 1 or 2, characterized in that

The reservoir (16) is arranged on the back side of the cartridge (1), and the plunger (2) pushes the expression means (15) into the reservoir (16) during movement in the direction of the back side of the cartridge (1).

26. Storage and mixing apparatus according to claim 25, wherein

The area between the expression device (15) and the plunger (2) is open towards the outside of the cartridge (1).

27. Storage and mixing apparatus according to claim 25, wherein

The plunger (2) is spaced from the expression means (15) such that when the plunger (2) is moved in a first section in the direction of the back side of the cartridge (1), a reduced pressure first builds up in the interior of the cartridge (1) without moving the expression means (15) and, in addition, when the plunger is moved in a second section, the expression means (15) is pushed into the reservoir (16).

28. Storage and mixing apparatus according to claim 25, wherein

The expression means (15) is a pump plunger and the reservoir (16) is a hollow cylinder, wherein the pump plunger is axially movable, wherein an extension is arranged on the upper side of the pump plunger, the outer diameter of the extension being smaller than or equal to the inner diameter of the interior of the cartridge (1), wherein the pump plunger with the extension is arranged in the hollow cylinder in such a way that the extension protrudes into the interior of the cartridge (1).

29. Storage and mixing apparatus according to claim 28, wherein

The extension is in the form of a cylindrical body.

30. Storage and mixing device according to claim 1 or 2, characterized in that

The reservoir (66) is delimited by a closed hollow cylinder (67) which is separate from the cartridge (51) and in which a pump plunger as an expression means (65) is supported axially movable, wherein the pump plunger is in circumferential and sealing contact with an inner wall of the hollow cylinder (67), wherein the hollow cylinder (67) is connected to the fluid line (56) at a first base and is connected to the interior of the cartridge (51) by a compressed gas line (69) or a hydraulic line (69) on the back side of the cartridge (51) at a second base, wherein the back side of the cartridge (51) is closed except for a mouth leading into the compressed gas line (69) or the hydraulic line (69), such that during movement of the plunger (52) in the direction of the back side of the interior of the cartridge (51), an overpressure or pressure is generated in the space between the plunger (52) and the rear side, which overpressure or pressure opens into the hollow cylinder (67) via the compressed gas line (69) or the hydraulic line (69).

31. Storage and mixing apparatus according to claim 30, wherein

The first substrate is a lower substrate and the second substrate is an upper substrate.

32. Method for mixing a parent component (4, 42, 54, 92) of bone cement using a storage and mixing device according to at least one of the preceding claims, the method being characterized by the following steps:

a) the plunger (2, 52) is moved in the direction of the rear side of the cylindrical interior of the cartridge (1, 51), wherein a reduced pressure is generated in the interior of the cartridge (1, 51) between the plunger (2, 52) and the cartridge head (3, 53) as a result of the movement of the plunger (2, 52),

b) -pushing the expression means (15, 65) into the reservoir (16, 66) due to the movement of the plunger (2, 52), whereby monomer liquid (42, 92) contained in the reservoir (16, 66) is pressed into the interior of the cartridge (1, 51) through the fluid line (6, 56) due to the movement of the expression means (15, 65),

c) mixing the monomer liquid (42, 92) and the first parent component (4, 54) in the interior of the cartridge (1, 51) to form the bone cement paste (44, 94), and

d) -expelling the bone cement paste (44, 94) from the interior of the cartridge (1, 51) by advancing the plunger (2, 52) in the direction of the cartridge head (3, 53).

33. The method of claim 32, wherein the step of determining the target position is performed by a computer

The bone cement is a two-component polymethylmethacrylate bone cement.

34. The method of claim 32, wherein the step of determining the target position is performed by a computer

Drawing the monomer liquid (42, 92) from the fluid line (6, 56) into the interior of the cartridge (1, 51) by the reduced pressure in the interior of the cartridge (1, 51).

35. A method according to claim 32 or 33, characterised in that

Introducing the monomer liquid (42, 92) into the reservoir (16, 66) prior to step a).

36. The method of claim 35, wherein the step of removing the metal oxide layer comprises removing the metal oxide layer from the metal oxide layer

Introducing the monomer liquid (42, 92) into the receptacle (16, 66) after a monomer liquid container (8, 58) has been opened in a container (7, 57) of the storage and mixing device.

37. A method according to claim 32 or 33, characterised in that

In step a), the plunger (2, 52) is pushed by means of a rod (9, 59) in the direction of the back side of the cartridge (1, 51), wherein the rod (9, 59) is movably supported in a gastight feed-through in the cartridge head (3, 53), and in step c) the monomer liquid (42, 92) is mixed with the first parent component (4, 54) by moving the rod (9, 59) and thus a mixing device (14, 64) connected to the rod (9, 59) in the interior of the cartridge (1, 51) between the plunger (2, 52) and the cartridge head (3, 53).

38. The method of claim 37, wherein the step of determining the target position is performed by a computer

The rod (9, 59) is movably supported in the delivery opening.

39. The method of claim 37, wherein the step of determining the target position is performed by a computer

Pulling the mixing device (14, 64) towards the cartridge head (3, 53) and removing a core material (10, 60) from the rod (9, 59) by means of the rod (9, 59) between steps c) and d) such that the rod (9, 59) without the core material (10, 60) forms a delivery conduit through which the mixed bone cement paste (44, 94) is pressed out of the interior of the cartridge (1, 51) in step d).

40. A method according to claim 32 or 33, characterised in that

Prior to step d), the cartridge (1, 51) is detached from the storage and mixing device and inserted into an extrusion device, in which step d) the plunger (2, 52) is pushed by means of the extrusion device in the direction of the cartridge head (3, 53) using a tappet or an advanceable rod, in order to expel the bone cement paste (44, 94) from the interior of the cartridge (1, 51).

41. A method according to claim 32 or 33, characterised in that

The reservoir (16, 66) is a hollow cylinder (67) and the expression means (15, 65) is a pump plunger arranged longitudinally movable in the hollow cylinder (67), wherein the pump plunger is moved in the hollow cylinder (67) by applying pressure with the plunger (2, 52) or pneumatically or hydraulically by means of an overpressure or pressure generated in the interior of the cartridge (1, 51) between the back side of the cartridge (1, 51) and the plunger (2, 52).

42. The method of claim 41, wherein the step of removing the metal oxide layer comprises removing the metal oxide layer from the metal oxide layer

The overpressure is passed into the hollow cylinder (67) via a compressed gas line (69) or the pressure is passed into the hollow cylinder (67) via a hydraulic line (69).

43. A method according to claim 32 or 33, characterised in that

Opening a monomer liquid container (8, 58) in the storage and mixing device prior to steps a) and b), wherein the monomer liquid (42, 92) flows out of the monomer liquid container (8, 58) and into the receptacle (16, 66).

44. The method of claim 43, wherein the step of removing the substrate comprises removing the substrate from the substrate

The monomer liquid (42, 92) flows into the reservoir (16, 66) through a screen (28, 78) and/or filter (28, 78).

45. The method of claim 43, wherein the step of removing the substrate comprises removing the substrate from the substrate

The monomer liquid container (8, 58) is a glass ampoule or a foil bag.